New OborWiki feature: Markdown output

The Markdown Output recipe is now installed on OborWiki (off by default; you can enable it via the Configurator). It allows you to render any page into Markdown format.

You can view the Markdown-rendered output of a wikipage (in place of the usual HTML-rendered version) by appending ?action=markdown to the URL. You can also modify Site.PageActions to add a new page action to display the Markdown version of any page.

(Remember that the Markdown Markup recipe, which allows the rendering of Markdown into HTML—i.e., lets you use Markdown in wikipages—is also available on OborWiki.)